Fix a hidden Publish Review button on the page.

Review Request #11544 — Created March 22, 2021 and submitted

Review Board

When the split Publish button was converted into the new
rb-c-menu-button component, it exposed a pre-existing problem where
the review draft banner (which is always present on a review request
page) was accepting events.

This wasn't a problem on 3.x, because we got lucky. Previously, on
3.x through 4.0 RC1, the banner was marked as hidden with a .hidden
class, and that enabled a visibility: hidden. This kept anything from
really happening in that banner.

The newer version regressed this due to a CSS rule for
rb-c-menu-button that unconditionally set visibility: visible on the
menu. This, along with some combination of the transform to keep it
off-screen and possibly the position: absolute or some other rule, was
keeping the visible menu off-screen but the events on-screen.

There's two bugs here:

1) rb-c-menu shouldn't have been set to visibility: visible inside
a menu button, unless the menu was open. This CSS rule has been
separated from another group of rules to ensure this.

2) The review banner should have been hidden from events entirely. This
is being handled by setting the hidden attribute, which will hide
the element and all children, no matter what, from the render tree,
event tree, and accessibility tree.

Tested all menu buttons in the UI to make sure they worked correctly,
and opened/closed correctly. Made sure they weren't able to receive
events when closed.

Tested that, with the above fix alone, the empty review problem was

Reverted that fix, and added fix #2, for the review banner's hidden state.
Verified that also solved the problem. Verified the review properly opened
when adding a new comment, and that publish/discard worked.

Tested the combination of both, making sure the issue was still fixed and
that the menu worked when the banner was open.

JavaScript unit tests passed.

Fix a hidden Publish Review button on the page.
  1. Yay!

Review request changed

Status: Closed (submitted)

Change Summary:

Pushed to release-4.0.x (d8fb308)